RequestSystem

@Override
public void tick()
{
    manager.getLogger().debug("Starting reassignment.");

    //Lets decrement all delays
    getAllAssignedRequests().forEach(t -> {
        Integer current = delays.remove(t);
        delays.put(t, --current);
    });

    //Lets get all keys with 0 residual delay:
    final Set<IToken<?>> retryables = delays.keySet().stream().filter(t -> delays.get(t) == 0).collect(Collectors.toSet());
    final Set<IToken<?>> successfully = retryables.stream().filter(t -> {
        final Set<IToken<?>> blackList = assignedRequests.get(t) < getMaximalTries() ? ImmutableSet.of() : ImmutableSet.of(id);

        Integer currentAttempt = assignedRequests.get(t);

        this.setCurrent(t);
        final IToken<?> resultingResolver;

        try
        {
            resultingResolver = manager.reassignRequest(t, blackList);
        }
        catch (Exception ex)
        {
            assignedRequests.remove(t);
            delays.remove(t);
            return false;
        }

        this.setCurrent(null);

        assignedRequests.put(t, ++currentAttempt);

        if (resultingResolver != null && !resultingResolver.equals(getId()))
        {
            assignedRequests.remove(t);
            delays.remove(t);
        }

        return resultingResolver != null;
    }).collect(Collectors.toSet());

    successfully.forEach(t -> {
        manager.getLogger().debug("Failed to reassign a retryable request: " + id);
    });

    manager.getLogger().debug("Finished reassignment.");
}